In a typical heating system, water is circulated by a pump through several radiators, possibly a heat exchanger in a hot water cylinder, and a boiler. During circulation, solid particles (for example, iron oxide) which have come loose from the interior of the radiators and pipework can become suspended in the water. Solid particles can also be present as contaminants in the water originally supplied to the system, and the water can become contaminated by dirt where an open expansion tank forms part of the system. These solid particles can cause malfunction if they build up in the boiler or pump, and reduce the effectiveness of the heating system by restricting the flow of water and clogging radiators. The water in a heating system should therefore be continually cleaned to remove solid particles as far as possible.
Various devices are known for removing particles from suspension in a flow of water. Typically these devices include a magnet for attracting ferrous particles, and may also include mechanical separation means for removing nonmagnetic particles. Nonmagnetic particles may be removed by causing a portion of the water to flow through a separation chamber, within which obstruction means are disposed to slow the flow. Particles will then fall out of suspension and become trapped in cavities, which can easily be cleaned during an annual service. Only a portion of the flow is slowed, so that the drop in fluid pressure across the device is minimized. Devices of this type are disclosed in the applicant's applications GB2486173 and GB2486172.
Known devices are designed to produce a slow flow rate in the separation chamber, whilst causing a minimal drop in fluid pressure across the unit. It is advantageous to produce separator devices which are small in size to enable them to be fitted in small spaces. This requires that the separator chamber must in turn be small in size, and the obstruction means disposed therein have a consequently limited ability to substantially slow the flow rate of fluid within. Since it is undesirable to place obstruction means outside of the separation chamber, due to the resultant pressure drop, there is a limit on the overall separation effectiveness of known devices.
When a heating system is serviced, the separator device must be cleaned to remove the particles which have been separated from the fluid. A removable screw-top is typically provided at the upper end of the cylindrical housing which, when removed, allows access to the inside of cylindrical housing. A removable insert is typically provided within the housing, which must be removed for cleaning.
The removable insert is typically of similar longitudinal extent to the cylindrical housing. Therefore to allow the insert to be removed from the housing, the separator device must be installed where there is a vertical space between horizontal surfaces of at least twice the height of the housing. This requirement imposes an unwelcome constraint on the installer in terms of where the device may be installed, particularly where the separator device is being retrofitted to an existing installation. For example, there is often insufficient space between the bottom of a boiler and a counter top. In some cases it may simply not be possible to fit a device of suitable capacity which requires such a large vertical space.
Separator devices are often fitted to a heating circuit via right-angle connectors which link the inlet and outlet of the device to pipework. The right-angle connectors may be installed on open ends of the pipework, and the separator device can then be pushed on to the right-angle connectors. However, cutting the pipe in exactly the right place and installing the right-angle connectors so that they correspond precisely with the inlet and outlet of the device is difficult to achieve. An installer may be tempted to attach the right-angle connectors to the separator device, afterwards screwing the connectors onto the pipework. However, there is a serious risk of damaging the separator device in this method, since the torque of a spanner on a right-angle connector may be sufficient to break an inlet or outlet port from the separator.